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authorGwendal Grignou <gwendal@chromium.org>2019-06-11 00:12:36 -0700
committerLee Jones <lee.jones@linaro.org>2019-07-02 12:11:31 +0100
commitecc2ca47f3cd5b5851496d8261b1b14463d4a726 (patch)
tree3d984dda8e7413aad9876979ce36f366c439a80b /drivers/mfd
parentac195d94280a783f030a01ee84998a198b779d99 (diff)
downloadlinux-ecc2ca47f3cd5b5851496d8261b1b14463d4a726.tar.bz2
mfd: cros_ec_dev: Register cros_ec_accel_legacy driver as a subdevice
With this patch, the cros_ec_ctl driver will register the legacy accelerometer driver (named cros_ec_accel_legacy) if it fails to register sensors through the usual path cros_ec_sensors_register(). This legacy device is present on Chromebook devices with older EC firmware only supporting deprecated EC commands: - Glimmer based devices [Intel SOC using LPC transport] - Veyron minnie devices [ARM SOC using SPI transport] Tested-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/mfd')
-rw-r--r--drivers/mfd/cros_ec_dev.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index a47223d2baf4..eb77bf6406f3 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -383,6 +383,72 @@ error:
kfree(msg);
}
+static struct cros_ec_sensor_platform sensor_platforms[] = {
+ { .sensor_num = 0 },
+ { .sensor_num = 1 }
+};
+
+static const struct mfd_cell cros_ec_accel_legacy_cells[] = {
+ {
+ .name = "cros-ec-accel-legacy",
+ .platform_data = &sensor_platforms[0],
+ .pdata_size = sizeof(struct cros_ec_sensor_platform),
+ },
+ {
+ .name = "cros-ec-accel-legacy",
+ .platform_data = &sensor_platforms[1],
+ .pdata_size = sizeof(struct cros_ec_sensor_platform),
+ }
+};
+
+static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
+{
+ struct cros_ec_device *ec_dev = ec->ec_dev;
+ u8 status;
+ int ret;
+
+ /*
+ * ECs that need legacy support are the main EC, directly connected to
+ * the AP.
+ */
+ if (ec->cmd_offset != 0)
+ return;
+
+ /*
+ * Check if EC supports direct memory reads and if EC has
+ * accelerometers.
+ */
+ if (ec_dev->cmd_readmem) {
+ ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1,
+ &status);
+ if (ret < 0) {
+ dev_warn(ec->dev, "EC direct read error.\n");
+ return;
+ }
+
+ /* Check if EC has accelerometers. */
+ if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
+ dev_info(ec->dev, "EC does not have accelerometers.\n");
+ return;
+ }
+ }
+
+ /*
+ * The device may still support accelerometers:
+ * it would be an older ARM based device that do not suppor the
+ * EC_CMD_GET_FEATURES command.
+ *
+ * Register 2 accelerometers, we will fail in the IIO driver if there
+ * are no sensors.
+ */
+ ret = mfd_add_devices(ec->dev, PLATFORM_DEVID_AUTO,
+ cros_ec_accel_legacy_cells,
+ ARRAY_SIZE(cros_ec_accel_legacy_cells),
+ NULL, 0, NULL);
+ if (ret)
+ dev_err(ec_dev->dev, "failed to add EC sensors\n");
+}
+
static const struct mfd_cell cros_ec_cec_cells[] = {
{ .name = "cros-ec-cec" }
};
@@ -488,6 +554,9 @@ static int ec_device_probe(struct platform_device *pdev)
/* check whether this EC is a sensor hub. */
if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
cros_ec_sensors_register(ec);
+ else
+ /* Workaroud for older EC firmware */
+ cros_ec_accel_legacy_register(ec);
/* Check whether this EC instance has CEC host command support */
if (cros_ec_check_features(ec, EC_FEATURE_CEC)) {